From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1828C433E5 for ; Thu, 16 Jul 2020 08:41:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D0B82067D for ; Thu, 16 Jul 2020 08:41:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chrisdown.name header.i=@chrisdown.name header.b="K87a2W3M" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727906AbgGPIlV (ORCPT ); Thu, 16 Jul 2020 04:41:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725867AbgGPIlU (ORCPT ); Thu, 16 Jul 2020 04:41:20 -0400 Received: from mail-ej1-x642.google.com (mail-ej1-x642.google.com [IPv6:2a00:1450:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5993C061755 for ; Thu, 16 Jul 2020 01:41:19 -0700 (PDT) Received: by mail-ej1-x642.google.com with SMTP id rk21so5713536ejb.2 for ; Thu, 16 Jul 2020 01:41:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chrisdown.name; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=ePof5wCzuT/mMHtRgUDVM1EIUctWdkAXKM6Kz2g0iK0=; b=K87a2W3M1tKldsF/dcPQZVPxvrrBTMLgnpMnwDbT8sQm6pX70EhwpbfmXf7SFXq4NB Sh8CRS6/unuz9krNhTtqR9t9K6PhkcN6U1IlTTCCu7Jii5M4catQhAaVYm3sbbGJ3Xen SnCBJmoS73Uo1Ok8Y8MpNOJQFRqMOFjEQcPl4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=ePof5wCzuT/mMHtRgUDVM1EIUctWdkAXKM6Kz2g0iK0=; b=bQ0YzZQq08MuHS3hyxpsuQ9+Y0Dsx6HJx5P2nCaDhNvo7gv/8rPCN/oJM1Cug0vlWP BH8fYHU44a42JquE3ETMk6/VHffH/iiXFcAU69wuA8rPXZCpfJaynsIlSICqEtYqCDTl HEK/KX2rvkspTyaWEiP5QxfP3xtyreuiieQ/AFvqPKAe15nsyijosJ7Wc59myDvPnLUe /kuV8kqiELBrercHdFTMpQOis4HGIBGfvqKwmZTncxCFS1a5MaQaelwxBjtwyCyjlqR/ EySX6sjaR5wMihvoXl6z4TpSxQYxqiQC/SFxf/vxF6oqrwrHglO/vj8ceGE6Eax9FziJ B1AA== X-Gm-Message-State: AOAM532GPsJYDi8RZPUincUXIC4uouxbxM1fde+0sNNH0JTluaZCjT8T uQ/EDFe1v1yM+w8KQ6+j2LQISpW0UlbAPA== X-Google-Smtp-Source: ABdhPJyKGM3tTyGDH10ixkWvGSjmxZo18x2ghnb9nUjKkUChbuDEeI7bqfjBC/MHX8AnyUUCPVcDrw== X-Received: by 2002:a17:906:7694:: with SMTP id o20mr2646459ejm.289.1594888878419; Thu, 16 Jul 2020 01:41:18 -0700 (PDT) Received: from localhost ([2620:10d:c093:400::5:a5b1]) by smtp.gmail.com with ESMTPSA id d12sm4728934edx.80.2020.07.16.01.41.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jul 2020 01:41:18 -0700 (PDT) Date: Thu, 16 Jul 2020 09:41:17 +0100 From: Chris Down To: Qu Wenruo Cc: Qu Wenruo , linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH v2 2/2] btrfs: qgroup: add sysfs interface for debug Message-ID: <20200716084117.GD2140@chrisdown.name> References: <20200715134931.GA2140@chrisdown.name> <20200716004031.GC2140@chrisdown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.14.6 (2020-07-11) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Qu Wenruo writes: > > >On 2020/7/16 上午8:40, Chris Down wrote: >> Qu Wenruo writes: >>> Would you please provide the full call trace (especially the address >>> causing the NULL pointer deref) and the reproducer (if possible)? >> >> I'll try to reproduce it again when I have time. I didn't have kdump >> set, and am not currently running linux-next, so until then, you can >> have this crappy photo that I rushed to take earlier before panic=30 >> took effect :-) > >The linux-next is using an older version of that patch, which has a bad >memory allocation inside atomic critical section. > >If you're unlucky enough, it could cause various weird bugs. >Thankfully, David has exposed it and the latest version in btrfs tree >should have it fixed. Great, thanks! When I run my tests again on linux-next I'll be sure to reapply the latest version of your patch first, then. Thanks, Chris